Disc drive suspension whose extending portion and flexure can be regulated

ABSTRACT

An extending portion of a hinge member is formed having a first hole in which a first positioning pin can be inserted and a second hole in which a second positioning pin can be inserted. The first hole has an elongated shape that allows the extending portion of the hinge member to move relatively to the first positioning pin in a width direction. The second hole is a circular large hole that allows the extending portion to move relatively to the second positioning pin in the width direction and an axial direction. A third hole and a fourth hole are formed in a flexure. The third hole has an elongated shape that allows the flexure to move relatively to the first positioning pin in the axial direction. The fourth hole has an elongated shape that allows the flexure to move relatively to the second positioning pin.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromthe prior Japanese Patent Application No. 2001-374534, filed Dec. 7,2001, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a disc drive suspension incorporated inan information processing apparatus such as a personal computer.

2. Description of the Related Art

FIG. 16 shows a part of a hard disc drive (HDD). This disc drivecomprises a plurality of suspensions 3 that individually supportmagnetic head portions 2 and actuator arms 4 that are mountedindividually with the suspensions. The magnetic head portions 2 serve torecord information on the respective recording surfaces of discs 1 foruse as recording media and read information from the discs 1. Theactuator arms 4 are turned around a shaft (not shown) by means of apositioning motor (not shown).

Each suspension 3 includes a base plate 5, a load beam 6 extending fromthe base plate 5 toward the head portion 2, a flexure 7, etc. A proximalportion 6 a of the load beam 6 is fixed on the base plate 5. The flexure7 is fixed on the load beam 6 by laser welding. A slider 8 thatconstitutes the head portion 2 is mounted on the distal end portion ofthe flexure 7.

The flexure 7, which is provided with a wiring portion, extends from thehead portion 2 toward the base plate 5 along the load beam 6. An endportion of the flexure 7 is fixed on an extending portion (not shown)that protrudes sideways from the proximal portion 6 a of the load beam6. External lead wires are connected (bonded) to electrode pads on theend portion of the flexure 7. Before bonding, therefore, the end portionof the flexure 7 must be fixed in advance in a predetermined position onthe extending portion.

If necessary, a step forming portion may be formed on the extendingportion by press working or the like. If the extending portion is thusformed having the step forming portion, its position and shape areliable to variation. If the end portion of the flexure is fixed in thepredetermined position on the extending portion that varies in positionand shape, stress such as tensile, compressive, or torsional stress isproduced in the flexure. If the stress is produced in this manner, therolling angle of the flexure cannot be within the range of a tolerance,and exerts a bad influence upon the properties of the suspension.

BRIEF SUMMARY OF THE INVENTION

Accordingly, the object of the present invention is to provide a discdrive suspension in which an end portion of a flexure can be fixed to anextending portion without producing excessive stress such as tensilestress in the flexure.

A suspension of the present invention comprises a load beam, a flexure,and an extending portion formed on a hinge member or the load beam.First and second holes are formed in the extending portion. Further,third and fourth holes are formed in the flexure. A first positioningpin can be inserted into the first and third holes. A second positioningpin can be inserted into the second and fourth holes. These positioningpins are provided on a jig.

The first hole is formed of an elongated shape that allows the extendingportion to move relatively to the first positioning pin in a widthdirection. The second hole is a large circular hole or the like thatallows the extending portion to move relatively to the secondpositioning pin in the width direction and an axial direction. The thirdhole is an elongated shape that allows the flexure to move relatively tothe first positioning pin in the axial direction. The fourth hole is anelongated shape that allows the flexure to move relatively to the secondpositioning pin in the axial direction. The axial direction describedherein is synonymous with the longitudinal direction of the suspension,and the width direction is the width direction of the suspension.

In the disc drive suspension that comprises the load beam, flexure,hinge member, etc., according to the present invention, the respectivepositions of the extending portion on the hinge member and the flexurecan be regulated, and excessive stress such as tensile stress can beprevented from being produced in the flexure.

In the suspension that is formed having the extending portion for fixingan end portion of the wired flexure to a proximal portion of the loadbeam, according to the present invention, moreover, the respectivepositions of the extending portion and the flexure can be regulated, andexcessive stress such as tensile stress can be prevented from beingproduced in the flexure.

In the disc drive suspension that comprises the load beam, flexure,hinge member, etc., according to the present invention, furthermore, therespective positions of the extending portion on the load beam and theflexure can be regulated, and excessive stress such as tensile stresscan be prevented from being produced in the flexure.

In the present invention, a longitudinal part of the flexure may bedesigned to pass over a slit formed in the hinge member.

Alternatively, in the present invention, an end portion of the flexuremay be formed extending rearward from the base plate mounting portion.According to this invention, a longitudinal intermediate portion of theflexure can be fixed on the extending portion.

In the present invention, moreover, the extending portion on the hingemember or the load beam may be formed having a step forming portion.According to this invention, the step forming portion of the extendingportion can prevent excessive stress such as tensile stress from beingproduced in the flexure despite variation in the accuracy of theextending portion.

Additional objects and advantages of the invention will be set forth inthe description which follows, and in part will be obvious from thedescription, or may be learned by practice of the invention. The objectsand advantages of the invention may be realized and obtained by means ofthe instrumentalities and combinations particularly pointed outhereinafter.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate presently preferred embodiments ofthe invention, and together with the general description given above andthe detailed description of the embodiments given below, serve toexplain the principles of the invention.

FIG. 1 is a plan view of a disc drive suspension according to a firstembodiment of the invention;

FIG. 2 is a sectional view of a part of a disc drive provided with thesuspensions shown in FIG. 1;

FIG. 3 is a plan view of a load beam of the suspension shown in FIG. 1;

FIG. 4 is a plan view of a base plate of the suspension shown in FIG. 1;

FIG. 5 is a plan view of a hinge member of the suspension shown in FIG.1;

FIG. 6 is a plan view of a flexure of the suspension shown in FIG. 1;

FIG. 7 is a sectional view of the suspension taken along line F7—F7 ofFIG. 1;

FIG. 8 is a side view of a part of the suspension taken in the directionof arrows F8 of FIG. 1;

FIG. 9 is a plan view schematically showing a part of the suspensionshown in FIG. 1 and a part of a jig;

FIG. 10 is a diagram showing the relation between the rolling angle ofthe suspension shown in FIG. 1 and the number of suspensions;

FIG. 11 is a diagram showing the relation between the rolling angle ofeach suspension as a comparative example and the number of suspensions;

FIG. 12 is a plan view of a suspension according to a second embodimentof the invention;

FIG. 13 is a plan view of a suspension according to a third embodimentof the invention;

FIG. 14 is a plan view of a suspension according to a fourth embodimentof the invention;

FIG. 15 is a plan view of a suspension according to a fifth embodimentof the invention; and

FIG. 16 is a sectional view of a part of a hard disc drive provided withconventional suspensions.

DETAILED DESCRIPTION OF THE INVENTION

A first embodiment of present invention will now be described withreference to FIGS. 1 to 9.

A hard disc drive (HDD) 10 shown in FIG. 2 comprises a plurality ofdiscs 11 for use as recording media, a plurality of suspensions 13having a head portion 12 each, actuator arms 14, etc. Each head portion12 serves magnetically to record on and read information from therecording surface of each disc 11. Each actuator arm 14 is an example ofan arm member to be mounted with each suspension 13. The actuator arms14 are turned around a shaft (not shown) by means of a positioning motor(not shown).

As shown in FIG. 1, each suspension 13 includes a load beam 20, a baseplate 21, a hinge member 22, a flexure 23, etc. As shown in FIG. 3, theload beam 20 has a proximal portion 30 and a distal end portion 31. Adimple 32 is formed on the distal end portion 31.

As shown in FIG. 4, a cylindrical boss portion 35 is formed on the baseplate 21. The boss portion 35 can be inserted into a mounting hole 36(shown in FIG. 2) of the actuator arm 14. The base plate 21 is fixed onthe actuator arm 14 by caulking (or plastically deforming) the bossportion 35 from inside.

As shown in FIGS. 1 and 5, the hinge member 22 has an end portion 40,flexible portions 42 elastically deformable in its thickness direction,base plate mounting portion 43, and extending portion 44. The endportion 40 is lapped and fixed on the proximal portion 30 of the loadbeam 20. The flexible portions 42 are formed individually on theopposite sides of an opening 41. The base plate mounting portion 43 islapped and fixed on the base plate 21. The extending portion 44 extendssideways from the mounting portion 43.

As shown in FIGS. 7 and 8, the extending portion 44 of the hinge member22 is formed having a step forming portion 45 that has a difference inlevel in the thickness direction. The step forming portion 45 is locatednear the base plate mounting portion 43.

As shown in FIG. 6, the flexure 23 has a metal base 50 and a wiringportion 51. The wiring portion 51 includes a conductive layer that isformed over the surface of the metal base 50 with an electricalinsulating layer between them. Thus, the flexure 23 is a so-called wiredflexure. The metal base 50 is formed of a metal sheet, e.g., a springystainless-steel sheet about 18 μm to 30 μm thick, as an example of amaterial that is thinner than the load beam 20. The flexure 23 extendsalong the load beam 20.

One end portion 55 of the flexure 23 is formed having a tongue portion56 that functions as a movable part and outrigger portions 57 and 58that are situated on the opposite sides, right and left, of the tongueportion 56, individually. The tongue portion 56 and the outriggerportions 57 and 58 can bend in the thickness direction of the flexure23. The tongue portion 56 can engage the dimple 32 on the distal endportion 31 of the load beam 20. A slider 59 (shown in FIG. 2) is mountedon the tongue portion 56. The slider 59 is provided with a transducer(not shown) for use as a magneto-electric transducer element. Thetransducer, slider 59, etc. constitute the head portion 12.

Electrode pads 66 are provided on the other end portion 65 of theflexure 23. The pads 66 are connected to external lead wires (notshown). The end portion 65 is lapped and fixed on the extending portion44 of the hinge member 22 by means of fixing means such as laser weldingor adhesive bonding. A first intermediate portion 67 and a belt-shapedsecond intermediate portion 68 are formed between the one and the otherend portions 55 and 65 of the flexure 23. The first intermediate portion67 overlaps the load beam 20. The second intermediate portion 68 issituated off the load beam 20.

As shown in FIGS. 5 and 9 and other drawings, the extending portion 44of the hinge member 22 is formed having first and second holes 72 and 74that are spaced in an axial direction X. First and second positioningpins 71 and 73 can be inserted into the first and second holes 72 and74, respectively.

The first hole 72 has an elongated shape. The hole 72 allows theextending portion 44 of the hinge member 22 to move relatively to thefirst positioning pin 71 for some distance in the width direction Y. Thehole 74 is a large-diameter circular hole. The hole 74 allows theextending portion 44 to move relatively to the second positioning pin 73for some distances in the width direction Y and the axial direction X.

As shown in FIGS. 6 and 9 and other drawings, the end portion 65 of theflexure 23 is formed having third and fourth holes 80 and 81. The holes80 and 81 are formed in positions spaced in the axial direction X. Thefirst positioning pin 71 can be inserted into the third hole 80. Thehole 80 has an elongated shape, which allows the end portion 65 of theflexure 23 to move relatively to the first positioning pin 71 for somedistance in the axial direction X.

The second positioning pin 73 can be inserted into the fourth hole 81.The fourth hole 81 also has an elongated shape, which allows the endportion 65 of the flexure 23 to move relatively to the secondpositioning pin 73 for some distance in the axial direction X.

The first and second positioning pins 71 and 73 are individuallyprovided on a jig body 85 (only a part of which is shown in FIG. 9). Thesecond positioning pin 73 can be moved in the axial direction X by meansof an adjusting mechanism (not shown). Thus, the distance between thepins 71 and 73 can be finely adjusted.

A frame portion S (only a part of which is indicated by two-dot chainline in FIG. 5) as a cuttable scrap portion is provided on an end of thehinge member 22. The frame portion S is held in a predetermined positionby means of a reference pin (not shown). The reference pin is situatedin a position separate from those of the positioning pins 71 and 73. Theframe portion S is cut from the hinge member 22 after the flexure 23 isfixed on the hinge member 22.

The intermediate portion 67 of the flexure 23 is fixed on the load beam20 by laser welding or adhesive bonding. The end portion 65 of theflexure 23 is fixed on the extending portion 44 of the hinge member 22by laser welding or adhesive bonding. As this is done, the extendingportion 44 of the hinge member 22 and the end portion 65 of the flexure23 are positioned by means of the positioning pins 71 and 73.

The base plate mounting portion 43 of the hinge member 22 is held in apredetermined position on the jig body 85 by means of the frame portionS and the reference pin. As shown in FIG. 9, the first positioning pin71 is inserted in the first hole 72 of the hinge member 22 and the thirdhole 80 of the flexure 23.

The second positioning pin 73 is inserted in the second hole 74 of thehinge member 22 and the fourth hole 81 of the flexure 23. The secondpositioning pin 73 can finely adjust the position of the jig body 85 inthe axial direction X. The position of the pin 73 is adjusted so thatthe pin 73 is situated substantially in the center of the second hole74.

The position of the extending portion 44 of the hinge member 22 in theaxial direction X is regulated by means of the first positioning pin 71in the first hole 72. Since the extending portion 44 is formed havingthe step forming portion 45 that is relatively roughly finished, theposition of the extending portion 44 may vary in the width direction Y,in some cases. Since the first hole 72 has an elongated shape thatextends in the width direction Y of the hinge member 22, however, it canabsorb the variation in the width direction Y.

The second hole 74 is a circular hole that has a diameter larger enoughthan the diameter of the second positioning pin 73. If the accuracy ofthe extending portion 44 varies owing to the presence of the stepforming portion 45, therefore, dislocations of the extending portion 44in the axial direction X and the width direction Y can be absorbed nearthe hole 74.

For the flexure 23, on the other hand, the first and second positioningpins 71 and 73 are inserted in the third and fourth holes 80 and 81,respectively. As this is done, the position of the end portion 65 of theflexure 23 in the width direction Y is regulated. The third and fourthholes 80 and 81 have elongated shapes that extend in the axial directionX of the flexure 23. Therefore, the position of the end portion 65 ofthe flexure 23 in the axial direction X can be regulated. Thus, the endportion 65 can be held in position without producing any excessivestress such as tensile stress in the flexure 23.

For these reasons, the flexure 23 can be prevented from being subjectedto excessive stresses, such as tensile, torsional, or compressivestresses when the end portion 65 of the flexure 23 is fixed on theextending portion 44. Thus, these stresses can be prevented fromexerting a bad influence upon the rolling angle of the flexure 23, sothat the performance of the suspension 13 can be prevented fromlowering.

FIG. 10 shows the result of measurement of the rolling angle of eachflexure 23 and the number of suspensions based on thirty manufacturedsuspensions 13. The respective rolling angles of the suspensions 13 wereall within a tolerance (Δθ)

FIG. 11 shows the result of measurement of the rolling angle of eachflexure and the number of suspensions based on thirty manufacturedsuspensions as comparative examples. In these comparative examples,holes that correspond individually to the holes 72, 74, 80 and 81 of theforegoing embodiment are all circular holes. The respective diameters ofthese circular holes are dimensions such that the positioning pins 71and 73 are just fitted in the holes. In many of the suspensions of thesecomparative examples, the rolling angle considerably exceeded thetolerance (Δθ).

FIG. 12 shows a suspension 13′ according to a second embodiment of theinvention. A proximal portion 30 of a load beam 20 of the suspension 13′overlaps a base plate 21. The proximal portion 30 of the load beam 20 isformed having an extending portion 90 and a step forming portion 91. Anend portion 65 of a flexure 23 is lapped and fixed on the extendingportion 90 by means of laser welding or with an adhesive agent.

The extending portion 90 is formed having first and second holes 72 and74 that are similar to the ones according to the first embodiment. Theend portion 65 of the flexure 23 is formed having third and fourth holes80 and 81 that are similar to the ones according to the firstembodiment. A first positioning pin can be inserted into the first andthird holes 72 and 80. A second positioning pin can be inserted into thesecond and fourth holes 74 and 81. Since the suspension 13′ resemblesthe suspension 13 of the first embodiment for other configurations,functions, and effects, common numerals are used to designate portionsthat are common to the two suspensions, and a repeated description ofthe common portions is omitted.

FIG. 13 shows a suspension 13A according to a third embodiment of theinvention. An end portion 40 of a hinge member 22 of the suspension 13Ais formed having a slit 22 a that extends in the longitudinal directionof the hinge member 22. The slit 22 a communicates with an opening 41.Junctions 22 b and 22 c for connection with the load beam 20 are formedindividually on the opposite sides of the slit 22 a. A longitudinal partof a flexure 23 is passed through the slit 22 a.

The hinge member 22 of the suspension 13A is formed having an extendingportion 44 and a step forming portion 45 that are similar to those ofthe suspension 13 of the first embodiment. An end portion 65 of theflexure 23 is lapped and fixed on the extending portion 44. Alongitudinal part of the flexure 23 extends from the base plate mountingportion 43 toward the extending portion 44 through the slit 22 a. Sincethe suspension 13A shares other configurations with the suspension 13shown in FIG. 1, common numerals are used to designate portions that arecommon to the two suspensions, and a repeated description of the commonportions is omitted.

FIG. 14 shows a suspension 13B according to a fourth embodiment of theinvention. A hinge member 22 of the suspension 13B is formed having anextending portion 44 and a step forming portion 45 that are similar tothose of the suspension 13 of the first embodiment. The extendingportion 44 is formed having first and second holes 72 and 74 that aresimilar to those of the suspension 13 shown in FIG. 1.

A flexure 23 of the suspension 13B has an intermediate portion 100 thatis lapped on the extending portion 44. The intermediate portion 100 isformed having third and fourth holes 80 and 81 that are similar to thoseof the suspension 13 shown in FIG. 1. The intermediate portion 100 isfixed on the extending portion 44. An end portion 65 of the flexure 23or electrode pads 66 extend rearward from the hinge member 22. Since thesuspension 13B shares other configurations with the suspension 13A shownin FIG. 13, common numerals are used to designate portions that arecommon to the two suspensions, and a repeated description of the commonportions is omitted.

FIG. 15 shows a suspension 13D according to a fifth embodiment of theinvention. A load beam 20 of the suspension 13D is provided with a baseplate mounting portion 20 a and a distal end portion 20 b on either sidean opening 41. The mounting portion 20 a is lapped on a base plate 21,and the distal end portion 20 b is situated nearer to a head portion 12.The circular base plate 21 is fixed on the base plate mounting portion20 a.

The base plate mounting portion 20 a is formed having a extendingportion 44 d and a step forming portion 45 d. Positioning holes 72 d and74 d are formed in the extending portion 44 d. The positioning holes 72d and 74 d have the same function with the first and second holes 72 and74 of the suspension 13 shown in FIG. 1. Since the suspension 13D sharesother configurations with the suspension 13B shown in FIG. 14, commonnumerals are used to designate portions that are common to the twosuspensions, and a repeated description of the common portions isomitted.

In carrying out the present invention, it is to be understood that thecomponents of the invention, including the positions and shapes of theextending portion and the first to fourth holes, as well as the specificforms of the load beam, hinge member, and flexure, may be variouslychanged and modified without departing from the scope or spirit of theinvention. Further, the invention may be also applied to a suspensionthat has no step forming portion.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details and representative embodiments shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalents.

What is claimed is:
 1. A disc drive suspension comprising: a load beamincluding a proximal portion and a distal end portion; a hinge memberincluding an end portion on which the proximal portion of the load beamis fixed, and a flexible portion elastically deformable in a thicknessdirection thereof; a flexure fixed on the load beam and including a headportion; an extending portion extending sideways from a base platemounting portion of the hinge member and having a part of the flexurefixed thereon; an elongated first hole formed in the extending portion,adapted have a first positioning pin inserted therein so as to allow theextending portion to move relative to the first positioning pin in awidth direction of the extending portion; a large-diameter second holeformed in the extending portion, adapted to have a second positioningpin inserted therein so as to allow the extending portion to moverelative to the second positioning pin in the width direction and in anaxial direction of the extending portion; an elongated third hole formedin the flexure, adapted to have the first positioning pin insertedtherein so as to allow the flexure to move relative to the firstpositioning pin in an axial direction of the flexure; and an elongatedfourth hole formed in the flexure, adapted to have the secondpositioning pin inserted therein so as to allow the flexure to moverelative to the second positioning pin in the axial direction of theflexure.
 2. A disc drive suspension according to claim 1, wherein alongitudinal part of said flexure passes over a slit formed in the hingemember.
 3. A disc drive suspension according to claim 1, wherein an endportion of said flexure extends rearward from the base plate mountingportion.
 4. A disc drive suspension according to claim 1, wherein saidextending portion comprises a step forming portion with a difference inlevel in the thickness direction of the extending portion.